This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Mucopolysaccharidosis type IT (MPSTI), also known as Hunter syndrome is a lethal lysosomal storage disorder characterized clinically by coarse facial features, skeletal deformities with short stature, joint contractures, hepatosplenomegaly, and cardiopulmonary deterioration. In severe cases, children experience profound mental retardation and die before the age of 15. Current treatments are limited to bone marrow transplantation (BMT) and enzyme replacement therapy (ERT) which is still under investigation. Both therapeutic approaches have disadvantages and therefore, alternative strategies need to be investigated.